Intuitive drive-by-wire steering with redundant mechanical control

ABSTRACT

A drive-by-wire steering system on a vehicle requiring counter-steering includes a driver input mechanism, for example, a steering wheel, joystick, voice command receiver, or keyboard, and a control system. A sensor receives driver input and sends that information to the control system. An engagement mechanism, for example, a clutch, separates the driver input mechanism from controlling the vehicle. The control system further includes at least one actuator, a wheel, and a mechanical linkage controllable via the engagement mechanism in order for the control system to articulate a steering mechanism, for example, the front wheel of the vehicle, as appropriate.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application is a divisional application of U.S. patent applicationSer. No. 14/537,835, filed Nov. 10, 2014, which claims the benefit ofU.S. Provisional Application No. 61/902,721, filed Nov. 11, 2013, thedisclosure of which is incorporated herein by reference in its entirety.

FIELD OF THE INVENTION

Embodiments of the invention generally pertain to transportationvehicles, and more particularly to vehicle steering systems.

BRIEF DESCRIPTION OF THE DRAWINGS

Non-limiting and non-exhaustive embodiments of the invention aredescribed with reference to the following figures, wherein likereference numerals refer to like parts throughout the various viewsunless otherwise specified. It should be appreciated that the followingfigures may not be drawn to scale.

Descriptions of certain details and implementations follow, including adescription of the figures, which may depict some or all of theembodiments described below, as well as a discussion of other potentialembodiments or implementations of the inventive concepts presentedherein. An overview of embodiments of the invention is provided below,followed by a more detailed description with reference to the drawings.

FIG. 1 is a block diagram of some of the components that may be includedin a vehicle to execute methods and processes according to an embodimentof the invention.

FIG. 2 is a block diagram for some components of a steering systemaccording to an embodiment of the invention.

FIG. 3 is an illustration of a steering system according to anembodiment of the invention.

FIG. 4 illustrates the components of a system controller as may be usedin accordance with an embodiment of the invention.

FIG. 5 illustrates a vehicle with gyro stabilized systems in whichembodiments of the invention are applicable.

DESCRIPTION

In the following description numerous specific details are set forth toprovide a thorough understanding of the embodiments. One skilled in therelevant art will recognize, however, that the techniques describedherein can be practiced without one or more of the specific details, orwith other methods, components, materials, etc. In other instances,well-known structures, materials, or operations are not shown ordescribed in detail to avoid obscuring certain aspects.

This patent relates to the field of vehicle steering, particularlyactive, drive-by-wire steering systems enhanced with a mechanicalredundancy for providing an intuitive user experience. Drivers primarilystabilize vehicle states during operation by changing vehicle speedsand/or counter-steering (i.e., for vehicles such as single-tracksystems, similar type track systems that utilize lateral stability whenstationary when or at low-speeds, or vehicles that articulates a lean).Counter-steering describes the concept where the driver is to first turnopposite from the direction which driver desires to go in order todestabilize the vehicle until the necessary lean is achieved. The driverthen corrects the steering toward the direction desired to guide thevehicle along the turn. Embodiments of the invention improves upon thiscounter-intuitive process that complicates the user experience invehicle operation.

Embodiments of the invention describe a vehicle control system thatincludes at least a driver input mechanism, at least one controlactuator, and one control processor/controller linked to at least two ormore wheels. The above components operate to counter-steer the vehicleas needed, implement gyroscopically stabilization, or implement acombination of counter-steering and gyroscope stabilization; theseoperations are performed in accordance with the driver's command(s) tomaintain stabilization without the need for driver to counter-steer. Thecontrol system translates user inputs (e.g., steering wheel angle andaccelerator pedal angle) to motor/actuator commands; these commands maybe used to simultaneously (or near simultaneously) track a yaw rate andvehicle speed and stabilize vehicle states (e.g., roll angle/rate, steerangle/rate, etc.).

The above embodiment may also comprise of a means of haptic feedback tothe driver to make the driving experience more intuitive to the driver.

The haptic feedback system indicates the control effort needed toperform the requested maneuver, as well as feedback from roadconditions. This is implemented as a responsive torque on the steeringactuation system (steering wheel, joystick, handlebars, etc.). As adriver inputs a desired steering angle, the haptic system will resistthe input proportional to the amount of control action necessary tocomplete said steering angle. Added to this torque will be feedback fromroad conditions to give the driver a sense of “road feel.” Hapticfeedback could be accomplished via a servo motor connected to the shaftof the steering wheel (before the mechanical clutch), and actuated bythe steering control system.

As described below with reference to the figures, embodiments of theinvention utilize drive-by-wire steering concepts. “Drive-by-wire”steering allows for more precise control of the vehicle; prior artsolutions have never applied drive-by-wire steering concepts to solvecounter-steering.

Embodiments of the invention further describe electronically controlleddrive-by-wire steering concepts that are additionally supported by amechanical fail-safe steering system. Thus, embodiments of the inventionmay or may not be enhanced by power/electrical components, or computerprocessing components (e.g., the components of a system controllerillustrated in FIG. 4).

By decoupling the driver input from the steering controls, embodimentsof the invention enables remote steering and allows for enhancement oroverride of driver inputs by supporting steering control commands sentfrom remote devices. Furthermore, the remote driver does not need toprovide counter steering commands to remotely operate vehicles with atrack system that utilizes lateral stability when stationary or when atlow speeds.

Embodiments of the invention describes methods and processes forenabling steering controls to substitutes the need for driver tocounter-steer. FIG. 1 is a block diagram of some of the components thatmay be included in a vehicle to execute said methods and processes.

Operations of said methods and processes include receiving user inputsfrom a steering mechanism (e.g., a steering wheel) via a sensor e.g., toindicate the steering wheel position), receiving vehicle stateinformation (e.g., vehicle speed, flywheel torque output, road wheelposition, feedback torque sensor) via sensors; receiving external data(e.g., road traction, weather effects) via sensors.

This data and sensor information are analyzed to determine how to getthe vehicle to respond according to the user's command. Command signalsare generated through direct input from the driver into the inputmechanism or are received from a remote command device to control atleast one of steering actuators, flywheels in gyroscopic stabilizationsystem or a combination of the two in order to actuate the direction ofthe vehicle directly in accordance to the user command.

With the above embodiment includes executing operations via electronicand sensor components, embodiments may also include a mechanicalembodiment for redundancy. Said mechanical embodiment may include: meansto reestablish, upon an electrical failure or driver command, theengagement mechanism the driver input mechanism to the road wheel andengage the mechanical gearbox employing mechanical means including anycombination or mechanical equivalent of a mechanical gearbox/planetarymechanism/levers component including gears, planetary mechanism, leverscomponents, or hydraulic pumps and piston to allow continual intuitivesteering for the driver.

FIG. 2 is a block diagram for some components of a steering systemaccording to an embodiment of the invention. FIG. 3 is an illustrationof a steering system according to an embodiment of the invention. Saidsteering systems may include a driver input mechanism (e.g., a steeringwheel, joystick, voice command receiver, keyboard, etc.), a sensor toreceive driver input and send information to the controls system, amechanical device to separate the driver input mechanism from vehiclecontrol (e.g., a clutch), an electronic control system, at least oneactuator and a wheel (e.g., a road wheel). The electronic control systemmay control the steering of the vehicle, as described herein.Furthermore, a mechanical linkage may be included that can beengaged/disengaged by employing the clutch-type mechanism in order forthe electric controls system to articulate the steering mechanism (i.e.front wheel) as appropriate. In some embodiments, upon the failure ofthe electrical system, the clutch engages the mechanical linkage so thedriver input mechanism may implement the mechanical fail-safe (describedabove) to continue to steer the vehicle without having to counter-steer.

Embodiments of the invention are applicable to vehicles with gyrostabilized systems (e.g., the vehicle illustrated in FIG. 5 anddescribes further below). Embodiments of the invention are alsoapplicable to vehicles without a gyroscopic system.

Embodiments of the invention may describe a control system including aprocessor, a memory module, and a control module stored in the memoryand executed via the processor. The control module may executeoperations to receive data from a plurality of sensors indicating driverinput, orientation of a frame of a vehicle, orientation of a front wheelof the vehicle with respect to the frame, orientations and rotationalspeeds of a plurality of flywheels included in a gyroscope unit coupledto the frame, and speed of the frame, determine a current vehicle statebased, at least in part, on the received data, and adjust an outputtorque of the gyroscope unit by adjusting a rotational velocity of atilt of at least one of the flywheels from an axis of rotation normal toan axis of rotation of the front a wheel of the vehicle based, at leastin part, on the current vehicle state. This adjustment of the outputtorque may include, but is not limited to: increasing the rotationalvelocity of the tilt of the at least one of the flywheels to increasethe output torque of the gyroscope unit, and minimizing the rotationalvelocity of the tilt in response to determining the current vehiclestate to use the output torque of the gyroscope unit for a prolongedperiod of time.

The control module may further adjust the direction of the front wheel(e.g., via an electronic signal command) to counter-steer for the driverwhile the mechanical linkage from the driver input mechanism to the roadwheel is disengaged (e.g., via a clutch).

FIG. 4 is an illustration of a computing device to execute a systemcontroller according to an embodiment of the invention. System 400 asillustrated may be any computing device to be included in a vehicle asdescribed herein. As illustrated, system 400 includes bus communicationmeans 418 for communicating information, and processor 410 coupled tobus 418 for processing information. The system further comprisesvolatile storage memory 412 (alternatively referred to herein as mainmemory), coupled to bus 418 for storing information and instructions tobe executed by processor 410. Main memory 412 also may be used forstoring temporary variables or other intermediate information duringexecution of instructions by processor 410. The system also comprisesstatic storage device 416 coupled to bus 418 for storing staticinformation and instructions for processor 410, and data storage device414 such as a magnetic disk or optical disk and its corresponding diskdrive. Data storage device 414 is coupled to bus 418 for storinginformation and instructions. In other embodiments, bus communicationmay be replaced with other communication networks.

The system may further be coupled to display device 420, such as acathode ray tube (CRT) or a liquid crystal display (LCD) coupled to bus418 through bus 426 for displaying information to a computer user. I/Odevice 422 may also be coupled to bus 418 through bus 426 forcommunicating information and command selections (e.g., alphanumericdata and/or cursor control information) to processor 410.

Another device, which may optionally be coupled to computer system 400,is a communication device 424 for accessing a network. Communicationdevice 424 may include any of a number of commercially availablenetworking peripheral devices such as those used for coupling to anEthernet, token ring, Internet, or wide area network. Communicationdevice 424 may further be a null-modem connection, or any othermechanism that provides connectivity between computer system 400 andother devices. Note that any or all of the components of this systemillustrated in FIG. 4 and associated hardware may be used in variousembodiments of the invention.

It will be appreciated by those of ordinary skill in the art that anyconfiguration of the system may be used for various purposes accordingto the particular implementation. The control logic or softwareimplementing embodiments of the invention can be stored in main memory412, mass storage device 414, or other storage medium locally orremotely accessible to processor 410.

Communication device 424 may include hardware devices (e.g., wirelessand/or wired connectors and communication hardware) and softwarecomponents (e.g., drivers, protocol stacks) to enable system 400 tocommunicate with external devices. The device could be separate devices,such as other computing devices, wireless access points or basestations, as well as peripherals such as headsets, printers, or otherdevices.

Communication device 424 may be capable of multiple different types ofconnectivity—e.g., cellular connectivity and wireless connectivity.Cellular connectivity refers generally to cellular network connectivityprovided by wireless carriers, such as provided via GSM (global systemfor mobile communications) or variations or derivatives, CDMA (codedivision multiple access) or variations or derivatives, TDM (timedivision multiplexing) or variations or derivatives, or other cellularservice standards. Wireless connectivity refers to wireless connectivitythat is not cellular, and can include personal area networks (such asBluetooth), local area networks (such as WiFi), and/or wide areanetworks (such as WiMax), or other wireless communication.

It will be apparent to those of ordinary skill in the art that thesystem, method, and process described herein can be implemented assoftware stored in main memory 412 or read only memory 416 and executedby processor 410. This control logic or software may also be resident onan article of manufacture comprising a computer readable medium havingcomputer readable program code embodied therein and being readable themass storage device 414 and for causing processor 410 to operate inaccordance with the methods and teachings herein.

FIG. 5 illustrates an inline two-wheeled vehicle incorporating one ormore embodiments of the invention. In this embodiment, vehicle 500comprises vehicle frame 502, and further includes first and second drivewheels 510 and 520.

In this embodiment, gyro stabilizing unit 530 is coupled to vehicle 500through vehicle frame 502. Gyro stabilizer 530 may include first andsecond gyro assemblies housing flywheels 532 and 534; said flywheels maydiffer in size and material composition, or may be substantiallyidentical.

Gyro stabilizer 530 may be controlled such that by utilizing more thanone axis of control over each gyro's flywheel, additional levels ofcontrol of the vehicle's orientation may be achieved. One controlleddegree of freedom, when lined up in a mutual orthogonal axis to thevehicles roll axis and the flywheel's rotation axis, may control thevehicle's roll. An additional degree of freedom allows for control overanother axis of rotation.

In some embodiments, gyro stabilizer 530 further comprises a turntableto increase the number of controllable axes of the flywheels. Forexample, flywheels 532 and 534 are illustrated to be coupled inline tothe vehicle frame (e.g., aligned lengthwise with respect to front wheel510 and rear wheel 520). Said turntable may change the alignment ofthese gyroscopes, to move their alignments towards being alignedwidthwise with respect to the frame of the vehicle.

Other embodiments may comprise of mechanisms to rearrange the positionof the gyro stabilizer array or adjust the alignment of the flywheelswith respect to height.

It is to be understood that the above description is intended to beillustrative, and not restrictive. Many other embodiments will beapparent to those of skill in the art upon reading and understanding theabove description. The scope of the disclosure should, therefore, bedetermined with reference to the appended claims, along with the fullscope of equivalents to which such claims are entitled.

Some portions of the detailed description above are presented in termsof algorithms and symbolic representations of operations on data bitswithin a computer memory. These algorithmic descriptions andrepresentations are the means used by those skilled in the dataprocessing arts to most effectively convey the substance of their workto others skilled in the art. An algorithm is here, and generally,conceived to be a self-consistent series of operations leading to adesired result. The operations are those requiring physicalmanipulations of physical quantities. Usually, though not necessarily,these quantities take the form of electrical or magnetic signals capableof being stored, transferred, combined, compared, and otherwisemanipulated. It has proven convenient at times, principally for reasonsof common usage, to refer to these signals as bits, values, elements,symbols, characters, terms, numbers, or the like.

It should be borne in mind, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities. Unlessspecifically stated otherwise as apparent from the discussion above, itis appreciated that throughout the description, discussions utilizingterms such as “capturing,” “transmitting,” “receiving,” “parsing,”“forming,” “monitoring,” “initiating,” “performing,” “adding,” or thelike, refer to the actions and processes of a computer system, orsimilar electronic computing device, that manipulates and transformsdata represented as physical (e.g., electronic) quantities within thecomputer system's registers and memories into other data similarlyrepresented as physical quantities within the computer system memoriesor registers or other such information storage, transmission or displaydevices.

Embodiments of the disclosure also relate to an apparatus for performingthe operations herein. This apparatus may be specially constructed forthe required purposes, or it may comprise a general purpose computerselectively activated or reconfigured by a computer program stored inthe computer. Such a computer program may be stored in a non-transitorycomputer readable storage medium, such as, but not limited to, any typeof disk including floppy disks, optical disks, CD-ROMs, andmagnetic-optical disks, read-only memories (ROMs), random accessmemories (RAMs), EPROMs, EEPROMs, magnetic or optical cards, or any typeof media suitable for storing electronic instructions.

Some portions of the detailed description above are presented in termsof algorithms and symbolic representations of operations on data bitswithin a computer memory. These algorithmic descriptions andrepresentations are the means used by those skilled in the dataprocessing arts to most effectively convey the substance of their workto others skilled in the art. An algorithm is here, and generally,conceived to be a self-consistent sequence of steps leading to a desiredresult. The steps are those requiring physical manipulations of physicalquantities. Usually, though not necessarily, these quantities take theform of electrical or magnetic signals capable of being stored,transferred, combined, compared, and otherwise manipulated. It hasproven convenient at times, principally for reasons of common usage, torefer to these signals as bits, values, elements, symbols, characters,terms, numbers, or the like.

It should be borne in mind, however, that all of these and similar termsare to be associated with the appropriate physical quantities and aremerely convenient labels applied to these quantities. Unlessspecifically stated otherwise as apparent from the above discussion, itis appreciated that throughout the description, discussions utilizingterms such as “capturing”, “determining”, “analyzing”, “driving”, or thelike, refer to the actions and processes of a computer system, orsimilar electronic computing device, that manipulates and transformsdata represented as physical (e.g., electronic) quantities within thecomputer system's registers and memories into other data similarlyrepresented as physical quantities within the computer system memoriesor registers or other such information storage, transmission or displaydevices.

The algorithms and displays presented above are not inherently relatedto any particular computer or other apparatus. Various general purposesystems may be used with programs in accordance with the teachingsherein, or it may prove convenient to construct a more specializedapparatus to perform the required method steps. The required structurefor a variety of these systems will appear from the description below.In addition, the present disclosure is not described with reference toany particular programming language. It will be appreciated that avariety of programming languages may be used to implement the teachingsof the disclosure as described herein.

Reference throughout this specification to “one embodiment” or “anembodiment” means that a particular feature, structure, orcharacteristic described in connection with the embodiment is includedin at least one embodiment of the present disclosure. Thus, theappearances of the phrases “in one embodiment” or “in an embodiment” invarious places throughout the above specification are not necessarilyall referring to the same embodiment. Furthermore, the particularfeatures, structures, or characteristics may be combined in any suitablemanner in one or more embodiments.

The present description, for purpose of explanation, has been describedwith reference to specific embodiments. However, the illustrativediscussions above are not intended to be exhaustive or to limit thedisclosure to the precise forms disclosed. Many modifications andvariations are possible in view of the above teachings. The embodimentswere chosen and described in order to best explain the principles of thedisclosure and its practical applications, to thereby enable othersskilled in the art to best utilize the various embodiments with variousmodifications as may be suited to the particular use contemplated.

Methods and processes, although shown in a particular sequence or order,unless otherwise specified, the order of the actions may be modified.Thus, the methods and processes described above should be understoodonly as examples, and may be performed in a different order, and someactions may be performed in parallel. Additionally, one or more actionsmay be omitted in various embodiments of the invention; thus, not allactions are required in every implementation. Other process flows arepossible.

1. A redundant mechanical steering system of a vehicle comprising: adriver input mechanism; at least one road wheel; an engagement mechanismthat mechanically engages the driver input mechanism to a steeringcontrol and the at least one road wheel of the vehicle; and a mechanicalgearbox/planetary mechanism/levers component including gears, planetarymechanism, levers components, or hydraulic pumps and piston; wherein theredundant mechanical steering system is a natural default upon anelectric failure of the vehicle.
 2. The system of claim 1, wherein thesystem may also be engaged upon driver command;
 3. The system of claim1, wherein, upon an electrical failure or driver command, the engagementmechanism is to reestablish the mechanical linkage throughout the driverinput mechanism to the road wheel and engage the mechanical gearboxemploying a combination of any of the gears, the planetary mechanisms,lever components or hydraulic pumps and piston to allow continualintuitive steering for the driver.